Storing data tables as metadata (table variables) JSL

Question

Table variables are used to store metadata within a data table (JSL doc, general doc)

However, they seem to be limited to variables as strings only (see code below).

What would be the best option to store a data table as a table variable?

Names Default To Here( 1 );

dt = Open( "$SAMPLE_DATA/Big Class.jmp" );

dt_metadata = Open( "$SAMPLE_DATA/Solubility.jmp" );

dt << Set Table Variable( "dt_user", dt_metadata );

close(dt_metadata);

dt_recovered = dt << Get Table Variable("dt_user");

show(dt_recovered);
show(Is String(dt_recovered));

//dt_recovered = "Solubility";
//Is String(dt_recovered) = 1;

hogi · Answer

For columns a user can specify column properties - and there is even a possibility to define user-defined properties.
How about a similar framework for tables?

Here is a wish :
General information about table

Craige_Hales · Answer

Or, if you mean to leave a link rather than embedding the data, perhaps use the file name for the linked table:

dta = New Table( "aa", New Column( "a", Numeric, "Continuous", Format( "Best", 12 ), Set Values( [1] ) ) );
dtb = New Table( "bb", New Column( "b", Numeric, "Continuous", Format( "Best", 12 ), Set Values( [2] ) ) );
dta << Save( "$temp/aa.jmp" );
dtb << Save( "$temp/bb.jmp" );

// leave table B's filepath in table A

dta << SetTableVariable("path to B", dtb<<getpath);

close(dtb);

dtb2 = open(dta:path to B); // apparently case matters with table variable names!

Craige_Hales · Answer

Here are three examples that embed the data for table B in table A . I prefer the dtb3 example for reasonable sized tables. The dtb4 example is what I think you described; it is maybe better for a huge B table, but it is very opaque to anyone else. dtb5 combines the two ideas.

// Make sample tables. When done, aa will have two table scripts and a table variable.
// the scripts and variables show three ways to embed bb in aa.
dta = New Table( "aa", New Column( "a", Numeric, "Continuous", Format( "Best", 12 ), Set Values( [1] ) ) );
dtb = New Table( "bb", New Column( "b", Numeric, "Continuous", Format( "Best", 12 ), Set Values( [2] ) ) );

// dtb3: I think you should do this with a table script because it can be
// opened from the GUI or from JSL. The downside is if the table is
// very large it will be slow to save and slow to open because it is
// making a script to recreate the table.
Eval( Eval Expr( dta << NewScript( "bbb", Expr( dtb << getScript ) ) ) );
// jsl to open:
dtb3 = Eval( dta << getScript( "bbb" ) );
dtb3 << SetName( "dtb3" ); // optional, was "bb 2"

// dtb4: it gets ugly with a table variable, there are several possibilities. This
// will save the table and grab the binary from the disk file and make a character
// string from that. You might choose to do this for a really large file, but I'm
// not sure what issues you'll run into. 
dtb << Save( "$temp/bb.jmp" );
blob = Load Text File( "$temp/bb.jmp", blob );
blob = Gzip Compress( blob );// optional
text = Char( blob );
dta << SetTableVariable( "bbbb", text );
// reopen
text = dta:bbbb;
blob = Parse( text );
blob = Gzip Uncompress( blob );//optional
dtb4 = Open( blob, "jmp" );
dtb4 << SetName( "dtb4" ); // optional, was "untitled"

// dtb5: you could combine the two ideas, saving the binary data as a table script so
// it can be used from the GUI
dtb << Save( "$temp/bb.jmp" );
blob = Load Text File( "$temp/bb.jmp", blob );
blob = Gzip Compress( blob );// optional
text = Char( blob );
Eval(
	Eval Expr(
		dta << NewScript(
			"bbbbb",
			Local( {text, blob, dt},
				text = Expr( text );
				blob = Parse( text );
				blob = Gzip Uncompress( blob );//optional
				dt = Open( blob, "jmp" );
				dt;
			)
		)
	)
);
// reopen 
dtb5 = Eval( dta << getScript( "bbbbb" ) );
dtb5 << SetName( "dtb5" ); // optional, was "untitled"